/Engine/Source/Developer/MaterialUtilities/Public/MaterialUtilities.h
Resizes flatten material's data if applicable by comparing it with the original settings
static void ResizeFlattenMaterial ( [FFlattenMaterial](API\Developer\MaterialUtilities\FFlattenMaterial) & InFlattenMaterial, const struct [FMeshProxySettings](API\Runtime\Engine\Engine\FMeshProxySettings) & InMeshProxySettings )